I think I'd actually enjoy being on the other end of the barrel. XD
There's not enough oomph there to really injure you, but it'd smart. I say try and build it dude. Couple bucks worth of PVC and some glue, along with diet coke and menthos (and parental supervision), and you've got a grade A science experiment that ends in explosions, soda, candy and launching projectiles.
I am the Chozon1.
And possibly, a booger
head. They'll let anyone on Soundclick